Spartanfam: go hard or go home

In person Chaka Clarke is not as physically daunting as you'd expect, despite his ripped physique. And for a man who can regularly be seen hanging sideways off whatever comes to hand – lampposts, scaffolding, his friends – performing a bodyweight exercise called the "human flag" that entails gripping a pole and holding yourself parallel to the ground, his dreams are very grounded. "Nowadays I don't think money is that important," says Clarke, who was recently snapped doing a handstand on the bonnet of a Rolls Royce Phantom he found in a car park at a party. His dreams involve not fantasies of excessive wealth, but parks.

Like others, I was drawn to Clarke's fitness family Spartanfam by pictures circulating on Twitter of him and the other Spartanfam trainers doing "the flag" together in a line. Bored of my gym routine, I was magnetised. I'd come across the pictures via the Run Dem Crew, a running club that meets at the Nike 1948 shop in Shoreditch, east London. The trajectory for all involved has been similar: the four Spartanfam trainers, Dwayne Cooper, Jamie Cox, Jermaine Etienne and Liam Etienne, all saw Clarke training on his own in Powis Square in Notting Hill and asked to join him. Then Charlie Dark, founder of Run Dem Crew, saw what they were doing and told Clarke to start a class.

That class now happens on Friday nights when the 50-plus Spartanfam members can be found in Shoreditch Park doing pushups, situps, planks, pullups, chinups, wheelbarrows, sprint drills and more, listening to music on a portable sound system. Clarke varies the intensity of sessions but for most of the time it's go hard or go home: I've learned that neither more pain nor being sick are anything to be afraid of. Sessions are so popular there is a waiting list. Clarke has also made a series of homework videos on YouTube, so that anyone can practise his bodyweight regime, anywhere. Neither bodyweight training nor park fitness are wholly new, but what makes Spartanfam, like Run Dem Crew, unique, is that it's about a way of life.

Raised in Coventry and then Leeds, Clarke came to London after the riots in Chapeltown, Leeds, on 8 August 2011. "It was nothing to do with the London riots – but the way they reported it on Sky News was: 'Houses are burning in Croydon and a man has been shot in Leeds.' When that happened my life changed a bit." Clarke had spent most of that year training in The Wreck skate park with his friends Gavin and Bubba, whom he met on returning to Leeds after serving with the army in Iraq. He was working as a personal trainer in a gym when Bubba invited him to train with them. "I'd go down to the park and there'd be eight or nine guys down there, all big looking, and no equipment." Instead they used nothing but the park apparatus and their own bodyweight. They would train from the early evening into the night.

In August 2011 they were training in the park when Gavin received a phone call and went off up the street. Shortly afterwards, Clarke heard a shot. He found Gavin stumbling around in the street, his face bleeding. Clarke used his military training to administer first aid, but the situation was grave. Before an ambulance had even arrived the police cordoned off the area, and riots broke out. Gavin died a few days later in hospital.

One thing still riles Clarke about it: "If these guys had just trained like the other boys who'd come down to the park with us this would have never have happened."

Clarke had learned his way of working things out in the army. With mortar alarms and camp excursions in Iraq constantly interrupting his fitness regime, he developed a more flexible approach: "I started doing pushups in my tent, pullups on the tank barrel and on the side of the bulldogs, the armoured fighting vehicles that we had, doing squat jumps, just messing about." And then there was his Sergeant Major, Carl Hilton. "He used to come to the gym and say "you're not really hard […] you can't even fight'." And so Hilton taught them how to box. In boxing, Clarke says, there is always a respect for your opponent.

"Training on your own is boring!", Clarke insists, and Spartanfam members Whitney Iles, 25, a social entrepreneur, and Infa Ford, 27, a PE teacher and sports coach, both say the best thing about the exercise club is the sense of "family". Iles says she's gone beyond her comfort zone, while Ford has rejected his previous weights/treadmill/protein drink routine: "Spartanfam has made me into an athlete," he says.

Spartanfam has just celebrated its first birthday, and is starting a new session in west London's Paddington Recreation Ground. Clarke is also helping to design a fitness-focused park that will open in Westminster later this spring. Clarke's dream of getting young people to train in parks across the country may well become a reality.

For more information about Spartanfam and to find out how to join, visit spartanfam.com